洛阳理工学院X80管线钢毕业设计.doc

X80液化石油管线钢焊接工艺研究 摘　要 随着全球能源需求的不断增加，石油天然气输送管道不断向高钢级、高压、大管径的方向发展。X80 管线钢是控轧控冷（TMCP）的微合金低碳钢，由于其钢材中马氏体和贝氏体独特的线性分布，使其在强度很高的条件下还保持了一定的塑韧性，成为管线建设的首选材料。 本文以X80钢的焊接工艺为研究对象，对高钢级管线钢的国内外应用情况，研究发展状况进行深入了解，并重点对X80管线钢焊接工艺设计过程、焊缝的组织性能分析，焊后热处理进行研究。采用显微镜组织观察，力学性能测试等方法，分析了解焊接过程中焊缝和热影响区金相组织的变化；结合接头组织性能分析，对焊接工艺设计参数进行优化，取得良好效果；并模拟焊后热处理（单一回火），探索焊后的优化焊接效果的措施。通过研究实验，从焊前、焊中、焊后各方面对X80管线钢的焊接工艺有了全面的了解。 关键词：X80管线钢，焊接工艺设计，金相分析，模拟热处理 X80 pipeline steel Studied on welding process ABSTRACT With the increasing of global energy demand, high grade steel, high pressure, large diameter oil and gas pipelines become the inevitable trend. X80 pipeline steel is controlled rolling and controlled cooling (TMCP) micro alloyed low carbon steel, due to its steel in martensite and bainite body the unique linear distribution, the under the condition of high strength also maintained a certain plasticity and toughness, become the material of choice for pipeline construction. This topic to X80 pipeline steel welding process is the research object, the high grade pipeline steel at home and abroad application, research and development status of in-depth understanding, and focus on X80 pipeline steel welding process design, weld microstructure and properties analysis, the welding simulation of heat treatment were studied. The microscope observation, mechanical properties test and analysis knowledge of welding microstructures of weld and heat affected zone crystal phase in the process of change; combined with the analysis of the microstructure and properties of welded joint, to optimize the design parameters of welding process, and achieved good results; and simulated post weld heat treatment (single tempered), explore welding after optimizing welding effect measures. Through experimental research, from all aspects of the welding process of X80 pipeline steel before welding, welding, after welding, have a comprehensive understanding of. KEY WORDS: X80 pipeline steel, Welding process, Metallographic analysis, Simula